Physics, Yes. But more?

Last summer, I worked at Sanfine International Hospital as an intern.

• I helped doctors to conduct patients’ mechanical analysis on their feet through a stress monitor to make accurate diagnosis, and recorded the pressure of static & dynamic equilibrium under crouching & standing positions to build proper medical rehabilitation insoles. Sometimes I worked as a translator, which enhanced my communication skills. I really enjoy this work because I saw how physics are closely related to medical fields, and how physics can benefit humans through different ways.
• Pressure mapping is a process that involves the use of specialized sensors to measure the distribution of pressure across the surface of the foot, particularly when standing, walking, or running. It is widely used in biomechanics, footwear design, sports science, and medical diagnostics.
• A foot pressure sensor is composed of two equipments: a pressure mat and a large screen that shows all the data. The pressure mat is a flat surface embedded with pressure sensors, commonly used for static and dynamic foot pressure analysis.

• 2D or 3D Pressure Map: A visual representation of the foot showing how pressure is distributed across the plantar surface. The map uses color coding to represent pressure intensity:
  • Blue/green areas: Indicate lower pressure zones, such as the arch or lighter weight-bearing areas.
  • Yellow/red areas: Highlight high-pressure zones, often at the heel or ball of the foot.
  • It helps identify areas of excessive pressure that may lead to discomfort, injuries, or conditions like ulcers (in diabetic patients).
• Center of Pressure (COP)
  • COP Pathline: This is a line or path that represents the movement of the center of pressure over time as you walk or stand.
  • It shows how weight shifts and transitions from heel to toe during walking.
  • A smooth COP line indicates normal foot mechanics, while deviations (e.g., excessive lateral or medial movement) may indicate gait abnormalities such as overpronation or supination.
• Center of Gravity (COG)
  • COG Line/Trajectory: In dynamic testing, the tool can show how the center of gravity moves in relation to the foot during gait or balance activities.
  • This line typically shifts as weight moves from the heel to the ball of the foot and toes during walking.
    Use: Analyzing the center of gravity helps in determining postural control, balance, and stability.
  • Postural sway: In standing positions, it can measure how much the center of gravity moves, which is important for balance assessments.
• Force Distribution
  • Force vs. Time Graphs: These graphs show how the force generated by the foot is distributed over time during each phase of walking (heel strike, midstance, toe-off).
  • Left vs. Right Foot Comparison: Many systems allow you to compare force distribution between the left and right feet to detect imbalances that may cause injury or discomfort.
  • It identifies asymmetries that may be present due to injury, surgery, or improper biomechanics.